Below is the official text of the Statement of the Consortium of Aquatic Science Societies (CASS) on the proposed replacement of the Waters of the United States (WOTUS) rule, cosigned by the PSA and eight other professional societies.

Aquatic Scientists Push Back Against Attempts to Replace Wetlands Rule

The Consortium of Aquatic Science Societies (CASS) is deeply concerned with the proposed rule issued today by the EPA and the U.S. Army Corps of Engineers to replace the 2015 Clean Water Rule (Waters of the United States Rule or WOTUS). We urge the agencies to consider the far-reaching implications to our nation’s fish and aquatic resources, wildlife and communities from a narrower rule and call for any re-definition of ”Waters of the United States” to be informed by science.

More than a half century of scientific research has unequivocally demonstrated that the physical, chemical, and biological integrity of “traditionally navigable” waters fundamentally depend on ephemeral, intermittent, and perennial headwater streams, as well as the myriad associated lakes, wetlands, and off-channel habitats.

Research specifically shows that downstream waters rely on headwaters and their associated wetland habitats for:

• uptake, retention, transformation and transport of nutrients and contaminants;

• control of runoff, streamflow and floodwaters

• moderation of water temperature and sediment delivery;

• food, thermal refuges, spawning sites, nursery areas and essential habitat for unique plants and animals, including numerous threatened and endangered species as well as recreationally and commercially important species.

Dr. Arnold van der Valk, Immediate Past President, Society of Wetland Scientists and a professor at Iowa State University, decried the decision by the Trump administration to replace the current WOTUS rule and noted, “It will result in the loss of many of the nation’s wetlands. This decision is short-sighted and counterproductive. It will significantly reduce the multitude of ecosystem services that these wetlands currently provide us at no cost. As a result the taxpayers will have to pay to build elaborate and expensive infrastructure to replace these free ecosystem services, such as flood reduction and cleaning up polluted water.”

Dr. Robert Twilley, Past President of the Coastal and Estuarine Research Federation and a professor at Louisiana State University, said: “Estuaries and coastal waters rely on clean water from upland watersheds to support productive, commercially, and recreationally valuable fisheries of the United States. The definition of ‘Waters of the United States’ was a joint effort of industry, private landowners, and government that recognized the importance of headland and other wetlands in providing the water quality that supports downstream economies.”

Dr. Douglas Austen, Executive Director of the American Fisheries Society (AFS), noted that “the 2015 Clean Water Rule provided a scientifically sound definition of ‘Waters of the U.S.’ The move to replace the rule puts America’s headwater streams and wetlands at greater risk of being destroyed or polluted and imperils fish and aquatic resources.”

CASS is composed of nine professional societies representing almost 20,000 individuals with diverse knowledge of the aquatic sciences. Those members work in the private sector, academia, non-governmental organizations, and various tribal, state, and federal agencies. CASS represents professional scientists and managers with deep subject matter expertise, a commitment to independent objectivity, and the critical review of environmental information. We support the development and use of the best available science to sustainably manage our freshwater, estuarine, coastal, and ocean resources to the benefit of the U.S. economy, environment, and public health and safety.